220株结核分枝杆菌北京临床分离株的基因分型研究

目的了解结核分枝杆菌北京临床分离株的基因分型种类和特征,为结核病防治研究提供基础科学依据。评价两种分型方法在北京地区结核病分子流行病学中的应用。方法收集北京市结核分枝杆菌临床分离株,应用间隔区寡核苷酸分型(Spoligotyping)及多位点可变数目串联重复序列分析(MLVA)二种分型方法进行基因分型,结果聚类分析采用BioNu-merics(Version5.0)软件。结果共在北京地区收集到220株结核分枝杆菌临床分离株。采用Spoligotyping分型方法,220株菌可分为2个基因群,即北京家族(Beijing family)和非北京家族(non-Beijing family),20种基因型。其中北京家族含有202株菌,占91.82%。北京家族菌株中,典型北京家族菌株占95.05%(192/202),非典型北京家族占4.95%(10/202)。北京家族菌株的耐药率为22.55%(22/98),非北京家族菌株的耐药率为16.67%(1/6),两者间的差异无统计学意义(fisher analysis,P=0.5835>0.05)。采用MLVA分型方法,202株菌可分成5个基因群59种基因型,主要为Beijing family、China2和China3,分别占91.37%、2.73%和4.55%。结论北京地区结核分枝杆菌具有明显的基因多态性,其主要流行型为北京家族。北京家族菌株与耐药性无明显相关性。

Genotyping analysis of 220 clinical isolates of Mycobacterium tuberculosis from Beijing area

To understand the class and characteristics of genotypes of Mycobacterium tuberculosis(M.tuberculosis)to provide the scientific basis for the prevention and treatment of tuberculosis,220 clinical isolates of M.tuberculosis from Beijing area were collected and their genotypes were investigated with spacer oligonucleotide typing(Spoligotyping)and multiple loci VNTRs(variable number tandem repeats)analysis(MLVA).Meanwhile,the results were analyzed by BioNumerics(version 5.0)software and statistical Fisher analysis.It was found that two genetic groups,i.e.Beijing family and non-Beijing family,could be demonstrated in these 220 strains of clinical isolates as detected by Spoligotyping,all-together displaying 20 genotypings,in which 202 strains were belonged to the Beijing family(91.82%).In the Beijing family,192 strains were typical Beijing family(9⒌05%)and 10 strains were atypical Beijing family(4.95%).In 98 strains of Beijing family and in 6 strain of non-Beijing family,22 and one strains were drug-resistant,respectively(22.55% and 16.67%),however,there was no significant difference as determined by Fisher analysis(P=0 5835,P>0 05).With MLVA,5 genetic groups were typed in 220 clinical isolates,displaying 59 genotypes,in which the chief genotypes were Beijing family(9⒈37%),China-2(⒉73%)and China-3(⒋55%).From this survey,it is evident that marked gene polymorphism exists in M.tuberculosis isolated from Beijing area,in which the Beijing family is the main and prevalent strain in Beijing area,but it has no significant correlation with drug resistance.